1. Field of the Invention
This invention relates to a system for guiding a forklift along a path.
2. Description of the Related Art
In a factory, warehouse, or other facility, when a forklift or other vehicle used for material handling is repeatedly moved along the same path, it may be desirable to install guide rails for the vehicle to constrain the vehicle to move along the path. The use of guide rails may be advantageous in that the operator need not steer the vehicle and can concentrate on manipulating the lifting equipment with which the vehicle is equipped. Furthermore, the guide rails can allow the vehicle to follow the path more precisely than would be possible were the operator steering the vehicle manually.
In one possible arrangement, guide rails can be disposed in parallel on the floor of the facility, with the spacing between the rails being slightly greater than the width of the vehicle measured at the wheels. The vehicle can be driven into the space between the rails, with the outer sidewall of each wheel of the vehicle facing and closely spaced from one of the rails. The vehicle can then be constrained by the rails to moving along a path parallel to the rails.
The above-described arrangement has a number of disadvantages. One is that the distance between the rails, which is dictated by the width of the vehicle, is such that a mechanical sweeper cannot fit between the rails, where dirt and other materials tend to accumulate. Therefore, it may be necessary to clean the space between the rails manually. Furthermore, since the rails guide the vehicle by contact with the side walls of the wheels of the vehicle, the wheels suffer considerable abrasion, which not only generates dust and other debris (such as rubber scraps when the wheels are equipped with rubber tires) but also decreases the lifespan of the wheels. In addition, since the separation between the rails must be wide enough for the wheels of the vehicle to freely pass between them, the sides of the wheels tend to bounce against the rails and may be dented or bent by the contact, with the extent of bending of the wheels often being severe enough to render it difficult to remove the wheels from the vehicle when it is necessary to replace the tires of the wheels.
The present invention provides a system for guiding a forklift along a path.
The present invention also provides an arrangement including a forklift and a system for guiding the forklift along a path.
The present invention also provides a method of operating a forklift.
According to one aspect of the present invention, a guide system for a forklift includes a single guide rail and a first pair of rollers between which the rail can pass mounted on the forklift.
According to another aspect of the present invention, a forklift includes a plurality of wheels, a body supported by the wheels, and a pair of rollers mounted on the body for engagement with a guide rail.
According to still another aspect of the present invention, a method of operating a forklift includes moving a forklift along a path while guiding the forklift with a guide rail passing between a pair of rollers mounted on the forklift.
A guide system according to the present invention preferably employs only a single guide rail, so the region of the floor of the facility in which the guide system is installed surrounding the guide rail can be easily cleaned using a power floor sweeper, with no accumulation of debris such as occurs with a two-rail guide system. Furthermore, the wheels on the forklift need not contact the guide rail, so they are not subject to wear or damage by the guide rail, and the guide rail is not subject to wear or damage by the wheels. In addition, the guide rail can guide the forklift extremely stably with little or no sideways wobbling of the forklift with respect to the rail.
While a guide system according to the present invention is particularly suited for use with a forklift, it can be employed with any vehicle which needs to be guided along a path.